Friction fabric and process for making same



May 18 1926.

J. A. HEANY FRICTION FABRIC AND PROCESS FOR MAKING SAME Filed Dec. 12,1923 2 Sheets-Sheet l I ATTORNEY May 18 1926.

J. A. HEANY FRICTION T43R10 AND PROCESS FOR MAKING SAME Filed Dec. 121923 2 Sheets-Shee .v 2

INVENTOR mm an; I.

ATTORNEY mental May is, 1926.

UNITED {EST/RATES PATENT OFFICE.

Join: ALLEN Ham, orf n'nw- HAVEN, conna'c'ricu'r, ASSIGNOIR- T0 WORLDnns'ros' coaroaa'rrom or ra'rnnsou, NEW JERSEY, A conroaa'rron orDELAWARE.

' rnrorrou Fann e AND rnoenss FOB, Maxine same.

' a pncauoii f a 'ea December 12,1923. Serial 1%. 680,186.

This invention relates to mateiials usable as friction elements, in anytypezof machinery but having particular utility, however, in connectionwith the brake mechanism of automotive vehicles.

In general, the invention comprehends the use in a friction fabric ofasbestos yarn formed of asbestos paper strip or tape, which ispreferably reinforced by one or more strands or filaments of metal orofa fibrous material, such as cotton, the fabric formed of the yarnbeing shaped and compressed to render the fabric relatively dense andclose in texture.

Among the objects of the, invention, therefore, is the provision of afriction fabric in which is embodied asbestos paper-like material as oneof the constituent elements.

Another important object is the provision of a friction fabric formed ofmaterial which is amenable to sha ing when subjected to pressure andwhich by compression tends to become smoothly compacted and brought to atexture highly suitable for use as brake lining material. I

Another object contemplated is the utilization in friction fabric ofyarn in which is embodied at least one strengthening element orfilament, either of metallic or of nonmetallic material, having greatertensile strength than the asbestos paper.

Another object involved is the employ-- ment of a fabric containingbinding material which may be readily loosened to permit working of thematerial and to permit adherent interengagement of the component yarns,and Whichsubsequentl will harden to give added tenacity and co erence t0the fabric. p

The above objects and other objects will become apparent fromconsideration of the mode of manufacture, which may .be preferred,hereinafter detailed and illustrated in the accompanying drawings inrelation specifically to brake lining fabrics, in which:

Fig. 1 is a View of the core'element of an illustrative form of yarnused in forming a friction fabric according to the present invention;

Fig. 2 is a view of asbestos tape used in the construction of such yarn;

Fig. 3 shows such yarn in completed form Fig. 4 is an enlarged detail ofa portion of a completed brake lining showing'the type of weave;

Fig. 5 is a detailed view ofa portion of the fabric formed in accordance'with the process of the present invent-ion;

Fig. 6 is adiagramatic showing of an apparatus for working .fabric afterit comes from the loom;

Fig. '7 is a diagrammatic view. ofa'modified arrangement of theapparatus shown in Fig. 6;

Fig. Sis a detail showing the specific type of calendering rollsemployed.

One form of yarn used in makin the fabric consists of a core element 10,which may be of metal,. as brass, or of cotton or of any material havingthe requisite tensile stren th, this core element being combined with asestos paper strip or band 11, to form the completed yarn 12, as shown inFig.3. The

method of application of the paper strip or band to the core is furtherbrought out in applicants co-pending applications as, for example, inapplication Serial No. 516,129, and need not be considered herein detailfurther than to state that the yarn making process includes generally amoistening step, and rubbing andtwisting steps and that generally two ormore strands are intertwistedv to give the requisite binding and holdingforce, although any one or more of these steps may be omitted, dependingupon the manufacturing requirements.

In the manufacture of, he asbestos yarns use maybe made of either longor short fibrcd asbestos material bound and formed into thin uniformpaper-like strips or bands of suificientcohesiveness and tenacity toundergo subsequent strand, yarn and fabric forming operations. Asdescribed in said co-pending'application, Serial No. 516,129, theasbestos material is formed into a pulp and passed through an ordinarypaper-making machine to form a, web which is rolled up in the usualmanner. This web, which in t e dere sufficiently dry and com act to havethe necessary strength, particu arly inthe surface portions thereof, isseparated preferably by a slitting machine into narrow strips or handsto be utilized in yarn manufacture. Satisfactory 'results in formingsaid strips are obtained by combining with the asbestos material in thepulp suitable binding material, which serves to increase the stren tllOfthe finished web or paper, thus renciring it suitable to withstand thestresses to which it is subjected in'yarn and fabric making operations.In practice, the strips, as they are fed from the slitting machine, arewound into fiat rolls for convenience in treating and handling thestrips or hands. The strips or bands are then united with filaments, asb rubbing, and further united therewith, as y twisting. The yarn, shownin Fig. 3, is supplied from la sufficient number of spools to form asheet of warp 'arns and this sheet is wound on a warp am which is thenput into a loom (not shown) of usual construction. Such warp yarnstogether with a woof yarn supplied from a shuttle are then woven intothe fabric having approximate dimensions of the brake lining desired.This fabric 13, Fig. 6, is carried over rollers 14 in a moistenedcondition the warp and the woof preferably being moistened just rior tothe -weaving operation, although in some instances, such moistening isomitted and the fabric comes throu h relatively dry. The material isthen led through pressure rolls 15, which in practice may be of suchshape as to determine the shape or size of the lining fabric and thenceover drying rolls 16 in the drying tower 17, through calendering rolls18, having a pressure regulating device 19 through the impregnating vat20 over guide rolls 21, thence through a second drying tower 22 overdrying rolls 23 through a second pair of calendering rolls 24 to reelingapparatus 25 where the fabric is in the final form of brake lining andready for use.

The first calender 18 may also serve to give size or form to thefabric,- the peripheries of the rolls having the conformationillustrated in Fig. 8. From this figure, it is evident that the lowerroll 26 has a flat periphery and the upper roll 27 has a flangedperiphery, the flanges 26 including the outer edge of the lower roll 26.The rolls 26 and 27 are sufficiently displaced relative to each other soas to permit the insertion of the brake lining 13 and due to the flanges28 of the uper roll, the fabric is boxed and consequenty sized orgauged, there being sufiicient pressure applied to square off the faceand the edge of the fabric and compact the material.

paper-making operation has been ren- I The pressure applied, however, inthe cal endering rolls {18 is insufficient to prevent absorption of theimpregnating fluid in the vat 20 through which the fabric is passed.

Any suitable impregnating solution may be employed such as linseed oilor gilsonite, and the fabric then thorou hly dried in the drying tower22. The fabric is then subjected to a second ressure o eration in thecalendering rol s 24 whic bring it to exact dimensions as required inthe trade and the completed brake lining is then reeled for storage orshipment.

paratus as utilized in the first form of the process.

In certain aspects, the present invention involves the process of makinasbestos friction fabric and the like, which consists in forming yarnsfrom paper-like strips of asbestos material bound with suflicientcohesiveness and tenacit to undergo subsequent strand, yarn and fa ricforming operations and adherently interengaging said yarns,

preferably by weaving, into a fabric; and also invo ves such resultingfabric. But in its broadest aspect the invention resides in an asbestosfabric or the like, combining asbestos material present in the fabric indeformed, flexible pa er-like stri formation, said material being oundtoget er with sufficient cohesiveness and tenacity to undergofabrication and to impart strength, cohesiveness and tenacity to thefabric.

It is important to note that the basic material of which the brakelining is composed is asbestos paper which is through the manu--facturing steps brought at least once to a softened or plasticcondition, but that the same retains its form by the employment ofcentering or holding cores. The susceptibility to softening permits thematerial to be readily compressed and sized to any degree of stiffnessor shape desired and, inasmuch as asbestos is non-lnflammable andlittle, if

any, inflammable substance is used in the manufacture of the fabric, thefinal brake lining is such as to meet the most rigid requirements ofactive practice. Asbestos fibre lends itself also readily toimpregnation and by the use of a proper impregnating solution, anadditional body is given the materialso that the final product is ahighly condensed, moisture impervious and retaining the'degree offlexibility desired by is apparent also that where the greatest tenthetrade. It is noteworthy also that it is not necessaryv touse long-fibredasbestos, although in manyinstances such use is desirable as due to thefact that the asbestos is formed as a paper strip in which the fibres ofasbestbs are held together by an adhesive binder, such as starch, it isimma-' terial whether the fibres of asbestos are short or long; Brakelining with asbestos of very short fibres has been used with markedsuccess.

It should be noted that the asbestos paperlike material is such that itmay be softened or rendei'ed more plastic by suitable treatment tofacilitate the manufacture of yarn and fabric. made from such yarn.After the fabric, is completed, it is treated to prevent such softeningor plastieizing and to give the fabric such characteristicsa's arenecessary for satisfactory service. In a specific form of carrying outthe invention; use is made of binding materialfincluding starch, whichmay be softened by moistening. The such capability of being softened bymoistening is, however, undesirable in thefinal fabric. The fabric istherefore treated or impregnated with some material such as linseed oilor gilsonite, which tends tow'atert proof the material and thereforetends to prevent softening or plasticizing of the paper-like materialflSuch impregnating .materials also possess certain lubricating qualitlesand serve to impart a certain degree of flexibility to the starch orother bind; ing material, which would otherwise become so stiff as tocrack easily in the yarn or finished fabricl lVhile I have describedbrake lining as being formed of a single strip of woven fabric, itisevident that a fabric of double or treble or any multiples of thedesired width may be used, the same being folded over and compressed tothe sizedesired. 1t

sile strength is desired,- it is'esseritial to use a metal reinforcedyarn and that insteadofusing a single strand of the same, the yarrrformed of several'strands twisted together, each strand having a metalcore, should be used. The fabric built up of yarns of this type whichhave been subsequently moist-' ened and impregnated and subjected to thepressure operations of the calender rolls, thus compacting the whole,will meet the severest requirements of brake lining usage.

It is obvious also that the fabric is not necessarily limited in itsuses to brake lining, but is usable as a friction element for anypurposes,"such, for example, as clutch facings. j

1 It should be understood that. the term asbestos material, wherever itappears in montziining a plurality the specification and claims, isintended to refer to material having 'a substantial percentage of'asbestos fibres, suclr as to give more or less the characteristics ofasbestos as far as Working and handling are concerned, and the termasbestos material where used in the specification and claims shall beconsidered-as thus defined.

While the invention has been described as relating to a specificapparatus and process and fabric resulting therefrom and as appliedspecifically to brake lining fabrics, it

should be understood that applicant does not hereby desire to limit theinvention to the specific means and elements detailed,

nor, to the use of the fabric alone to brake lining, but to include suchsubject matter and equivalents as come into the scope of the claimshereunto ,appended.

What is claimed is:

1. An asbestos friction fabric or the like,

containing a plurality of interengagell and deformed paper-like stripsof asbestos material bound with suflicient cohesiveness and tenacity toundergofabrication, said str ps being present in the fabric inpaper-like formation.

2. An asbestos friction fabric or the like of interengaged strips ofasbestos material present in deformed paper-like strip formation, eachof said strips being bound together by binding material with sufficientcohesiveness and tenacity to undergo fabrication.

3. An asbestos friction fabric or the like, containing asbestos materialpresent in the fabric in deformed, flexible paper-like formation, saidmaterial being bound together with sufiicient cohesiveness and tenacityto undergo fabrication and to impart durability and tenacity tothefabric.

4. An asbestos friction fabric or ,the like, containing compacted andreinforced asbestos material present in the fabric in creased ordeformed, flexible paper-like formation, the fibres of said materialbeing united along their entire longitudinal lengths and bound togetherwith suflicient cohesiveness and tenacityto undergo fabrication and toimpart durability and coherence tb the fabric.

5. An asbestos friction fabric 101' the like, containing asbestosmaterial present in the fabric in deformed, flexible paper-likeformation, said material being bound together by binding material withsufficient cohesiveness and tenacity to undergo fabrication andto impartdurability and coherence to the fabrim c 6. An asbestos friction abrioorthe like,

containing a plurality O of interengaged strips of asbestos material,each .of $3.16. strips being bound by binding material with suflicientcohesiveness and tenacity to undergo fabrication and to impart cohesiveness, tenacity and strength to the fabric, and each of said strips alsobeing present in the fabric in deformed, flexible paper-like formation.

7. An asbestos friction fabric or the like, containing asbestos materialpresent in flexible paper-like formation, said material being boundtogether by binding material with sufiicieiit cohesiveness and tenacityto underg0 fabrication and having reinforcing filaments associatedtherewith to impart strength, tenacity and cohesiveness to the fabric.

8. An asbestos friction fabric or the like, containing a plurality ofinterengaged strips of asbestos material present in deformedflexiblepaper-like strip formation, each of said strips being formed and boundtogether by binding material with sufficient cohesiveness and tenacityto undergo fabrication and having one or more reinforcing filaments,combined therewith to impart strength, tenacity and cohesiveness to thefabric.

9. An asbestos friction fabric or the like,

containing a plurality of compacted, flexible and inter-engaged stripsof asbestos, material longitudinally arranged therein and present indeformed paper-like formation; the fibres of said strips being unitedalon their entire longitudinal lengths and mind together with sufficientcohesiveness and tenacity to undergo fabrication" and to impartcohesivcness,- tenacity and strength to the fabric.

10. An asbestos friction fabric or the like, containing a plurality ofcompacted, flexible and interengaged strips of asbestos materiallongitudinally arranged therein and present in deformed paper-likeformation, the fibres cohesiveness and tenacity to undergo fabricationand with one or more reinforcing filaments combined therewith to impartstrength, tenacity and cohesiveness to the fabric. 4

12. An asbestos friction fabric or the like,

containing a plurality of closely compacted,

- flexible and interengaged strips of asbestos material longitudinallyarranged therein and present in' longitudinally and transverselycreasedor deformed flexible paper-like formation, each of said stripshaving the fibres thereof united along their entire longitudinal lengthsand bound closely together by binding material with suflicientcohesiveness and tenacity to undergo fabrication and also having one ormore reinforcing filaments associated therewith to impart strength,tenacity and cohesiveness to the fabric.

13; An asbestos friction fabric orthe like,

containing yarns formed from paper-like strips of asbestos materialbound together with suflicient cohesiveness and tenacity to undergosubsequent strand, yarn and fabric 1 forming operations.

14. An asbestos friction fabric or the like, the major portion of whichcomprises adhering yarns formed from paper-like strips of asbestosmaterial bound together with suflicient cohesiveness and tenacity toundergo subsequent strand, yarn and fabric forming operations.

. 15. An asbestos friction fabric or the like, the major portion ofwhich comprises yarns, each of which is formed from a filamenttwistedpvith a paper-like strip of asbestos material bound together withsuflicient cohesiveness and tenacity to undergo subsequent strand, yarnand fabric forming operations.

16. An asbestos friction fabric or the like,

the inajo'r, portion of which comprises adhering yarns formed frompaper-like strips of asbestos material bound together with suflicientcohesiveness and tenacity to under:

.go subsequent strand, yarn and fabric forming operations, andreinforcing filaments combined with said strips.

17. An asbestos friction fabric or the like composed of interengagedyarns, the major portion of the yarns of said fabric comprisingpaper-like strips of asbestos material bound together with suflicientcohesiveness and tenacity to undergo subsequent strand, yarn and fabricforming operations.

18. A woven asbestos friction fabric or the like, the warp threads ofwhich comprise adhering yarns formed from paperlike strips of asbestosmaterial bound together with suflicient cohesiveness and tenacity toundergo-subsequent strand, yarn and fabric forming operations, andreinforcing filaments combined with said strips.

19. An asbestos friction fabric or the like composed of adherentlyinterengaged yarns, each of said yarns being formed fro-m at least onefilament twisted with at least one paper-like strip of asbestos materialbound together with sufficient cohesiveness and tenacity to undergosubsequent strand, yarn and fabric forming operations.

20. An asbestos friction fabric or the like, the warp threads of whidhcomprise adhering yarns formed from paper-like strips of asbestosmaterial bound together with sufficient cohesiveness and tenacity toundergo associated with said strips.

21. An asbestos friction fabric or the like composed of a plurality ofadhering yarns, each of said yarns comprising a filament combined with apaper-like strip of asbestos material having workable binding-materialtherein.

22. An asbestos friction fabric or the like comprising yarns, the majorportion of which comprises adhering yarns formed from paper-like stripsof asbestos material bound together with workable binding material withsuflicient cohesiveness and tenacity to undergo subsequent strand, yarnand fabric forming operations.

23.' The process of making asbestos friction fabric and the like, whichcomprisesthe following steps: of forming asbestos material united withworkable binding material into paper-like strips or hands of sufficientcohesiveness and tenacity to undergo subsequent strand, yarn and, fabricforming operations; of forming yarns from said strips or bands; ofadherently interengaging -such yarnslrto form a fabric; and ofthereafter ,compacting said fabric.

24. ,The process of making asbestos friction fabric and the like, whichcomprises the following steps: of forming asbestos material united" withworkable binding -material into paper-likestrips or bands of sufficientcohesivene and tenacity to undergo subsequent strand, yarn and fabricforming op-' erations; of forming yarns from said strips or bands; ofinterengaging such yarns to .form a plastic fabric; of com acting saidfabric while in plastic conditlon; and of destroying its plasticcondition.

25. The process of making asbestos friction fab icand the like, whichcomprises the followin g steps: of forming asbestos material united withworkable binding material into paper-like strips or bands of sufficientcohesiveness and strength to undergo subsequent strand,.yarnand fabricforming operations; of uniting said strips or hands with filaments toform yarns; of interengaging and moistening such yarns to form a fabric;

of compressing said fabric while in a moistened condition; and of dryingsaid fabric.

26. The process of making asbestos frictiori fabric and the like, whichcomprises the following steps: of forming asbestos 'mate rial unitedwith workable binding material into paper-like strips or bands ofsufficient cohesiveness and tenacity to undergo subse-' ,quentstrand,,yarn and fabric forming. op-

erations; of'moistening said strips orbands to render" the bindingmaterial more 'work- ,able;-of uniting the moistened. strips withfilaments; to form p yarns; of interengaging such yarnsgwhile moist toform afabric;

tion fabric or the like, which comprises the of compressing said fabricwhile moist; and of drying said fabric.

27 The process of making asbestos frictionfabric or the like, whichcomprises the following steps: of binding and forming asbestosmaterialinto paper-like strips or bands of sufficient cohesiveness andtenacity to undergo subsequent strand, yarn and fabric formingoperations; of forming asbestos yarns from said strips or bands/whileretaming' the strip or band formation there- 111; and of adherentlyinterengaging yarns, including such asbestos yarns, to form a fab- I'1ccontaining a substantial proportionof asbestos material.

28. The process of making asbestos friction fabric or the like, whichcomprises the following steps: of forming asbestos material united withworkable bindin material into paper-like strips or bands of sufiicientcohesiveness and tenacity to undergo subsequent strand, yarn and fabricforming operations of forming asbestos yarns from said strips or bands;of interenga 'ng yarns, including such asbestos yarns, form a plasticfabric containing a substantial proportion of asbestos material; ofcompacting said fabric while in plastic condition;and

of destroying such plastic condition.

29. The process of making asbestos fricfollowing steps: of binding andforming asbestos material into paper-like strips or bands of sufficientcohesiveness and tenacity to undergo subsequent strand, yarn and fab ricforming operations; of uniting said Strips or bands with filaments toform asbestos yarns; and of adherently interengaging yarns, includingsuch asbestos yarns, to form a fabric containing a substantialproportion of asbestos material.

30. The process of making asbestos friction fabric or the like, whichcomprises the. 'followin steps: of formin asbestos material united withworkable binding material into paper-like strips orbands ofsufiicientcohesiveness and tenacity to undergo subsequent strand, yarn and fabricformin operations; of moistening said strips or ands to render thebinding material more workable; of uniting the moist strips orbands withfilaments to form moist asbestos yarns; of interengaging yarns,including such moist asbestos yarns to forma moist asbestos fabric Icontaining a substantial proportion of asbestos material; of compressingsaidfabric while moist; and ofdrying said fabric.

31. The process of making asbestos friction fabric or the like, whichcomprises the following steps: of binding and forming asbestos materialinto paper-like strips or 125 bands of sufficient cohesiveness andtenacity to undergo subsequent strand, yarn and fabric formingoperations; of uniting said I forming reinforced yarn from filamentsand,

said fabric:

following steps: of binding and forming as- I bestos material intopaper-like strips or bands of sufficient cohesiveness and tenacity toundergo sub equent strand, yarn and fabric forming oyierations; offorming asbestos yarns from said strips or bands; of moistening andbinding warps of such asbestos yarn into a moist fabric; and ofcompacting said fabric While in moistened condition.

33. The process of making asbestos friction fabric or the like, whichcomprises the following steps: of forming asbestos material united withworkable" binding material into a paper-like strip or band of sufficientcohesiveness and tenacity to undergo subsequent strand, yarn and fabricforming operations; of uniting at least one of such strips or bands withat least one filament to form an asbestos yarn; of interengaging andmoistening yarns,,including such asbestos yarns, to form a fabriccontainin a substantial proportion of asbestos material; and ofcompressing said fabric while ina moistened condition.

34. The process of making asbestos friction fabric and the like, whichconsists in,

forming yarn from paper-like strips of as bestos material united withworkable bind ing material, moistening said yarn, formingsa1d yarn wh lemoist into a fabric, and subsequently compressing and drying the fabr1c.35.-The process of manufacturing asbestos friction fabric and the like,which consists in forming reinforced yarn from cores and paper-likestrips of asbestos material'bound with suflicient cohesiveness andtenacity to undergo subsequent strand, yarnand fabric formingoperations, moistening the yarn, forming said yarn while moist into, afabric, and su sequently compressing and drying V36.'The process ofmaking asbestos friction fabric and the like, which consists in mo stpaper-like strips of asbestos material bound with sufficientcohesiveness and tenacity to undergo subsequent strand, yarn and fabricforming operations, forming said yarn while moist into a fabric, andsubjecting said fabric to pressure and drying operations.

37. The process of making asbestos fric tion fabricand the like,'whichconsists in forming yarns-from paper-like strips of asbest m erial bounth. s fi ien 0 hesiveness and tenacity to undergo subsequent strand,yarn and fabric forming operations, and adherently interengaging saidyarns into a fabric.

38. The process of making asbestos friction fabric and the like, whichconsists in forming yarns from paper-like strips of asbestos materialbound with sufficient cohesiveness and tenacity to undergo subsequentstrand, yarn and fabric forming operations, formlngsaid yarns into afabric,

and effecting an adherent engagement be-.

tween individual yarns.

39. The process of making asbestos friction fabric and the like, whichconsists in forming yarns from paper-like strips of asbestos materialbound by workable binding material with suflicient cohesiveness andtenacity to undergo subsequent strand, yarn and fabric formingoperations, weaving said yarns into a fabric, and effecting anadherentengagement between individual yarns.

4=O.'The process of making asbestos friction fabric or the like, whichincludes forming asbestos material united with binding material, whichmaybe softened or plasticized, into paper-like strips or bands ofsuflicient cohesiveness and tenacity and adapted for yarn manufacture;forming asbestos yarns from such strips or bands; interengaging yarns,including such asbestos \yarn, to form a fabric containing a substantialroportion of asbestos material; and treating said fabric to preventsubsequent softening or plasticizing of the binding material and toimpart greater durability to the fabric. w

41. A'fiexible asbestos friction fabric or the like, containingreinforcin filaments combined with asbestos paper-1i e material presentin the fabric in paperlike fonnation, said material being bound withsufficient cohesiveness and tenacity to undergo fabrication.

42. A flexible asbestos friction fabric or the like, a substantialproportion of the weft,

threads of which consists of yarns formed from one or more reinforcingfilaments com-- warp threads of which consists of yarns formed. from oneor more reinforcing filaments combined with asbestos material present inthe fabric in paper-like formation,

and bound with sufiicient cohesiveness and tenacity'to undergo strandand yarn manufacture. i

44. A flexible friction fabric, containing asbestos material present inpaper-like for-] mation and bound together with sufficient 00-hesiveness and tenacity to undergo fabrication and to retain its paer-like characteristics. in the fabric, an reinforcing fila ments orstrands assoc-iated'with said asbestos material for reinforcing saidfabric.

45). A friction fabric or the like, including longitudinal filaments andweft yarn formed from asbestos paper-like material bound with suflicientcohesiveness and te- 10 nacity and adapted for yarn manufacture.

46. A friction fabric or the like, including longitudinal filaments andweft yarn formed from at least one filament and at least one strip orband of asbestos material bound together with sufficient cohesivenessand tenacity and adapted for yarn manufacture.

In testimony whereof; I affix my signature.

JOHN ALLEN HEANY.

